58 



CORA D. REEVES 



tropis cornutMs), 7-10 cm. in length. The apparatus was 

 in a room illuminated by daylight. 



Counts of respiration rate in diffused daylight gave 

 about 60 per minute. The respiration rate of a quiescent 

 fish was then taken while the artificial light in the box 

 was shining upon it, and gave 85 per minute. A ruby 

 glass was then placed in front of the carbon lamp. The 

 effect of this was to change the quality of the light to which 

 the fish was exposed but to lessen its intensity. The respira- 

 tion rate in this less intense illumination by red light was 

 found to be increased to 150. 



b. Other characteristic behavior of fish in the presence of 

 stimulus patches of unfamiliar light of long wave-length. 



(1) Sunfish. In describing the red-blue training ex- 

 periments I have already referred to the peculiar avoidance 

 of red shown by sunfish unaccustomed to it. During the 

 first weeks of the experiments in which the blue and red 



Fig. 17 



Path of Large Sunfish in the experiment aquarium to show the effect of red light 

 on its movements. The red illuminated region is bounded above by the straight 

 broken line. For explanation see text. 



